1. Technical Field
The present disclosure relates to valve assemblies for catheter systems. More particularly, the present disclosure relates to valve assemblies including linear actuation mechanisms for rotating a ball-valve to open and close a fluid passageway within the assemblies.
2. Background of Related Art
Access catheters may be single lumen, dual lumen or multi-lumen and may be used for a variety of procedures, including dialysis and urine collection. The main body of the catheter is designed for operable engagement with a patient and the proximal or outer end includes extensions, one for each lumen. It is common practice to make these extensions from flexible tubing so that the tubing may be manipulated outside the body and held in any convenient position using surgical dressings. The tubing generally carries a luer lock connector at its free end for attachment to fluid lines and for subsequent closing and sealing of the lumens when the catheter is not in use. Because these connectors have a tendency of failing, it is also common practice to place a clamp on each of the extensions to deform the tubing and to act as a second closure mechanism.
Flexible tubes and clamps are unsatisfactory for use in access catheters for a number of reasons. The most serious problem is that, because the clamps close the tubing through a pinching action, if the clamp is in place for a significant length of time, the tubing may not recover when the clamp is released. The resulting crease in the tubing causes flow problems, and in extreme cases, the catheter has to be removed because the tube is no longer patent. This problem is most prevalent on catheters that have thermoplastic tubular extensions made from polyvinylcholoride (PVC) or polyurethane (PU).
It has also been found that unless the clamps used to pinch closed the tubing are aligned accurately before engaging the tubing, the clamps may disengage by a minor impact. Furthermore, conventional clamps tend to have sharp edges which are required to crease the tubing. These sharp edges may result in cutting and/or shearing of the tubing, particularly when silicone rubber tubing is used.
Accordingly, a continuing need exists for a valve assembly for use in an access catheter that includes at least one actuation mechanism for regulating the flow through the catheter without detriment to the catheter or tubing.